Stroke risk assessment for atrial fibrillation: hospital-based stroke risk assessment and intervention program

Despite the proven effectiveness of antithrombotic therapy for atrial fibrillation (AF), the treatment remains suboptimal. The aim of this study was to implement and evaluate a system to improve the appropriate use of antithrombotics for stroke prevention in AF utilizing a clinical pharmacist as a stroke risk assessor.

Hospital in-patients with AF were prospectively identified and they received a formal stroke risk assessment from a pharmacist. The patients' risk of stroke was assessed and documented according to Australian guidelines and a recommendation regarding antithrombotic therapy was made to the medical team on a specially designed stroke risk assessment form.

One hundred and thirty-four stroke risk assessments were performed during the intervention period. For those patients at high risk of stroke and with no contraindication present (warfarin-eligible patients), 98% were receiving warfarin on discharge from hospital compared to 74% on admission (P < 0.001). Of the 50 (37%) assessments that recommended a change of therapy, 44 (88%) resulted in a change in the patient's current antithrombotic therapy compared to their admission therapy. Thirty (68%) of the assessments resulted in an 'upgrade' to more-effective treatment options for example from no therapy to any agent or from aspirin to warfarin.

The pharmacist-led stroke risk assessment program resulted in a significant increase in the proportion of patients receiving appropriate thromboprophylaxis for stroke prevention in AF. The methods used in this study should be evaluated in a larger trial, in multiple hospitals, with different pharmacists performing the intervention.